1. Field of the Invention
The present invention relates to an insulating joint for use in a rail system to electrically isolate parts of the rail system from each other.
2. Description of the Prior Art
A rail system is generally divided into sections or blocks to be able to detect trains which permits more trains to travel on one stretch of track or rail. Each section is electrically isolated from all other sections so that when no train is present in the section, a high electrical resistance can be measured over the parallel railbars in the section. When a train enters a section, the train short circuits adjacent railbars and the electrical resistance drops.
Railbars are generally welded to each other or attached to each other by a steel joint. High performance non-metallic joints are used for electrically isolating two railbars in order to build an electrically isolated section. Switches are insulated in the same way by dividing both gauge plate and switch rods into two parts and by joining the respective parts with a non-metallic joint.
Known non-metallic joints are very expensive because of the special high performance material which has to endure high tensile and flexural forces. One such non-metallic material used for the joints is a laminated SCOTCHPLY.RTM. material manufactured by 3M of St. Paul, Minn. In addition, a separate insulating plug must be utilized between ends of the gauge plate or switch rod to prevent material buildup of debris which would then cause an electrical short.
An object of the present invention is to provide an insulating joint whereby the above drawbacks are eliminated.